Agriculture remained the foundation of Late Prehistoric economy, but something was different. The kinds of foods did not change. Corn, beans, and squash were staples. But towns and villages were smaller, and the far-flung Mississippian culture was replaced by a variety of local cultures with more differences than seen before. In some areas, there seem to have been no residents at all during late prehistory. Trade networks shrank and some disappeared. By the end of the period, Late Prehistoric people in southeastern Illinois had acquired European artifacts. This is the first sign of Native Americans greatest challenge. After 12,000 years of adapting to the challenges of nature and neighbors, Native Americans struggled to maintain their way of life while coping first with European demands for land and fur, and later the ravages of European diseases.